小续命汤有效成分组对慢性脑缺血大鼠脑线粒体的保护作用

Effects of the effective component group of Chinese herbal medicine Xiaoxuming Decoction on brain mitochondria in rats with chronic cerebral ischemia

目的:观察小续命汤有效成分组对慢性缺血大鼠脑线粒体的作用,研究小续命汤有效成分组抗慢性脑缺血的作用机制。方法:采用双侧颈总动脉永久性结扎法建立慢性脑缺血大鼠模型。将造模成功大鼠分为慢性脑缺血模型组、银杏叶提取物组和低、中、高剂量小续命汤有效成分组,另取假手术大鼠设为对照组,每组6只。采用梯度离心法提取大鼠脑线粒体,Clark氧电极法测定新鲜线粒体的呼吸功能,吸光光度法测定线粒体肿胀度,罗丹明123染色检测线粒体膜电位,蛋白质印迹法检测线粒体凋亡情况。结果:与假手术组大鼠相比,慢性脑缺血大鼠脑线粒体呼吸功能显著降低,表现为磷氧比值和氧化磷酸化效率显著降低;慢性脑缺血大鼠脑线粒体膜电位显著下降,肿胀度显著增高,细胞色素c释放增加,Bcl-2/Bax比率下降。小续命汤有效成分组治疗可改善慢性脑缺血引起的大鼠脑线粒体损伤。结论:小续命汤有效成分组可显著改善慢性脑缺血导致的脑线粒体结构和功能的损伤,这可能是小续命汤抗慢性脑缺血作用的机制之一。

OBJECTIVE： To investigate the effects of the effective component group of Xiaoxuming Decoction （XXM）, a compound traditional Chinese herbal medicine, on cerebral mitochondria in rats with chronic cerebral ischemia. METHODS： Rats were subjected to permanent bilateral common carotid artery occlusion to induce chronic cerebral ischemia. Then, the rats with chronic cerebral ischemia were randomly divided into five groups： model group, extract of Ginkgo biloba group and low-, medium- and high-dose effective component group of XXM groups. Another 11 rats without common carotid artery occlusion were used as a sham control. Gradient centrifugation was used to obtain the mitochondria from the rat brain. Clark oxygen electrode method was used to determine mitochondrial respiratory function. Photometric determination was used to measure mitochondrial swelling. Rodamine 123 was used to measure mitochondrial membrane potential. Western blotting was used to detect mitochondrial apoptosis. RESULTS= Compared with the sham group, the mitochondria dysfunction was caused by chronic cerebral ischemia associated with the decrease of oxidative phosphorylation parameters and the mitochondrial membrane potential, the increase of the mitochondrial degree, the elevation of reactive oxygen species level, the decrease in Bcl-2/Bax ratio, and the release of cytochrome c. The effective component group of XXM could reduce mitochondrial damage induced by chronic cerebral ischemia by improving the indexes mentioned above. CONCLUSION： The effective component group of Xiaoxuming Decoction can protect brain mitochondrial homeostasis and improve the function of mitochondria in rats with chronic cerebral ischemia, which may be the mechanism of its protection against chronic cerebral ischemia.